Activators of the GIRK family of Potassium Channels (hERG_ThalliumFlux_CRC)

GIRK potassium channels are a family of inward-rectifying potassium channels also known as the Kir3 family. They are expressed as homo and heterotetramers in with specific subunit combinations expressed in different brain regions and peripheral organ systems notably including the heart. Multiple lines of evidence support important roles for GIRK in a variety of physiological processes including more ..

BACKGROUND: GIRK potassium channels are a family of inward-rectifying potassium channels also known as the Kir3 family. They are expressed as homo and heterotetramers in with specific subunit combinations expressed in different brain regions and peripheral organ systems notably including the heart. Multiple lines of evidence support important roles for GIRK in a variety of physiological processes including the control of heart rate and electrical excitability in a variety of neuronal populations. Data concerning GIRK's role in neurons suggest GIRK as a potential target for a variety of therapeutic indications including pain, epilepsy, and reward/addiction. However, a complete lack of selective and effective GIRK activators has prevented any further target validation for the many indications where GIRK activation is speculated to be of potential benefit. And, although GIRK small molecule GIRK inhibitors are known, their lack of selectivity limits their utility as research tools or potential therapeutics for such indications as atrial fibrillation.

PURPOSE:The purpose of this assay was to test the concentration-dependent efficacy of putative GIRK 1/2 activators in a cell line that expressed the voltage-gated potassium channel, hERG in order to determine the selectivity of the GIRK activator probe, SID 135363148, for a more distantly related potassium channel family member.